1/* 2 * Copyright (C) 2011 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27#include "CrossfadeGeneratedImage.h" 28 29#include "FloatRect.h" 30#include "GraphicsContext.h" 31#include "ImageBuffer.h" 32 33namespace WebCore { 34 35CrossfadeGeneratedImage::CrossfadeGeneratedImage(Image* fromImage, Image* toImage, float percentage, const FloatSize& crossfadeSize, const FloatSize& size) 36 : m_fromImage(fromImage) 37 , m_toImage(toImage) 38 , m_percentage(percentage) 39 , m_crossfadeSize(crossfadeSize) 40{ 41 setContainerSize(size); 42} 43 44static void drawCrossfadeSubimage(GraphicsContext* context, Image* image, CompositeOperator operation, float opacity, const FloatSize& targetSize) 45{ 46 FloatSize imageSize = image->size(); 47 48 // SVGImage resets the opacity when painting, so we have to use transparency layers to accurately paint one at a given opacity. 49 bool useTransparencyLayer = image->isSVGImage(); 50 51 GraphicsContextStateSaver stateSaver(*context); 52 53 context->setCompositeOperation(operation); 54 55 if (useTransparencyLayer) 56 context->beginTransparencyLayer(opacity); 57 else 58 context->setAlpha(opacity); 59 60 if (targetSize != imageSize) 61 context->scale(FloatSize(targetSize.width() / imageSize.width(), targetSize.height() / imageSize.height())); 62 context->drawImage(image, ColorSpaceDeviceRGB, IntPoint()); 63 64 if (useTransparencyLayer) 65 context->endTransparencyLayer(); 66} 67 68void CrossfadeGeneratedImage::drawCrossfade(GraphicsContext* context) 69{ 70 // Draw nothing if either of the images hasn't loaded yet. 71 if (m_fromImage == Image::nullImage() || m_toImage == Image::nullImage()) 72 return; 73 74 GraphicsContextStateSaver stateSaver(*context); 75 76 context->clip(FloatRect(FloatPoint(), m_crossfadeSize)); 77 context->beginTransparencyLayer(1); 78 79 drawCrossfadeSubimage(context, m_fromImage, CompositeSourceOver, 1 - m_percentage, m_crossfadeSize); 80 drawCrossfadeSubimage(context, m_toImage, CompositePlusLighter, m_percentage, m_crossfadeSize); 81 82 context->endTransparencyLayer(); 83} 84 85void CrossfadeGeneratedImage::draw(GraphicsContext* context, const FloatRect& dstRect, const FloatRect& srcRect, ColorSpace, CompositeOperator compositeOp, BlendMode blendMode, ImageOrientationDescription) 86{ 87 GraphicsContextStateSaver stateSaver(*context); 88 context->setCompositeOperation(compositeOp, blendMode); 89 context->clip(dstRect); 90 context->translate(dstRect.x(), dstRect.y()); 91 if (dstRect.size() != srcRect.size()) 92 context->scale(FloatSize(dstRect.width() / srcRect.width(), dstRect.height() / srcRect.height())); 93 context->translate(-srcRect.x(), -srcRect.y()); 94 95 drawCrossfade(context); 96} 97 98void CrossfadeGeneratedImage::drawPattern(GraphicsContext* context, const FloatRect& srcRect, const AffineTransform& patternTransform, const FloatPoint& phase, ColorSpace styleColorSpace, CompositeOperator compositeOp, const FloatRect& dstRect, BlendMode blendMode) 99{ 100 std::unique_ptr<ImageBuffer> imageBuffer = ImageBuffer::create(size(), 1, ColorSpaceDeviceRGB, context->isAcceleratedContext() ? Accelerated : Unaccelerated); 101 if (!imageBuffer) 102 return; 103 104 // Fill with the cross-faded image. 105 GraphicsContext* graphicsContext = imageBuffer->context(); 106 drawCrossfade(graphicsContext); 107 108 // Tile the image buffer into the context. 109 imageBuffer->drawPattern(context, srcRect, patternTransform, phase, styleColorSpace, compositeOp, dstRect, blendMode); 110} 111 112} 113